It's not far from the design of a Champ. It could be wired to be a little more bass friendly, but you've got low plate voltage, limited B+ filtering, and about 5 watts. It could be made into a better guitar amp, but it would still be just a few watts. It has a pretty small output transformer to boot. You could put in a SS rectifier to get the voltage up some, and that would allow you to increase the B+ cap, which would aid a little in headroom.